**Slither** is a Solidity & Vyper static analysis framework written in Python3. It runs a suite of vulnerability detectors, prints visual information about contract details, and provides an API to easily write custom analyses. Slither enables developers to find vulnerabilities, enhance their code comprehension, and quickly prototype custom analyses.
If you're **not** going to use one of the [supported compilation frameworks](https://github.com/crytic/crytic-compile), you need [solc](https://github.com/ethereum/solidity/), the Solidity compiler; we recommend using [solc-select](https://github.com/crytic/solc-select) to conveniently switch between solc versions.
We recommend using a Python virtual environment, as detailed in the [Developer Installation Instructions](https://github.com/trailofbits/slither/wiki/Developer-installation), if you prefer to install Slither via git.
### Using Docker
Use the [`eth-security-toolbox`](https://github.com/trailofbits/eth-security-toolbox/) docker image. It includes all of our security tools and every major version of Solidity in a single image. `/home/share` will be mounted to `/share` in the container.
```bash
docker pull trailofbits/eth-security-toolbox
```
To share a directory in the container:
```bash
docker run -it -v /home/share:/share trailofbits/eth-security-toolbox
* For GitHub action integration, use [slither-action](https://github.com/marketplace/actions/slither-action).
* To generate a Markdown report, use `slither [target] --checklist`.
* To generate a Markdown with GitHub source code highlighting, use `slither [target] --checklist --markdown-root https://github.com/ORG/REPO/blob/COMMIT/` (replace `ORG`, `REPO`, `COMMIT`)
3 | `array-by-reference` | [Modifying storage array by value](https://github.com/crytic/slither/wiki/Detector-Documentation#modifying-storage-array-by-value) | High | High
4 | `encode-packed-collision` | [ABI encodePacked Collision](https://github.com/crytic/slither/wiki/Detector-Documentation#abi-encodePacked-collision) | High | High
5 | `incorrect-shift` | [The order of parameters in a shift instruction is incorrect.](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-shift-in-assembly) | High | High
6 | `multiple-constructors` | [Multiple constructor schemes](https://github.com/crytic/slither/wiki/Detector-Documentation#multiple-constructor-schemes) | High | High
7 | `name-reused` | [Contract's name reused](https://github.com/crytic/slither/wiki/Detector-Documentation#name-reused) | High | High
8 | `protected-vars` | [Detected unprotected variables](https://github.com/crytic/slither/wiki/Detector-Documentation#protected-variables) | High | High
9 | `public-mappings-nested` | [Public mappings with nested variables](https://github.com/crytic/slither/wiki/Detector-Documentation#public-mappings-with-nested-variables) | High | High
10 | `rtlo` | [Right-To-Left-Override control character is used](https://github.com/crytic/slither/wiki/Detector-Documentation#right-to-left-override-character) | High | High
11 | `shadowing-state` | [State variables shadowing](https://github.com/crytic/slither/wiki/Detector-Documentation#state-variable-shadowing) | High | High
12 | `suicidal` | [Functions allowing anyone to destruct the contract](https://github.com/crytic/slither/wiki/Detector-Documentation#suicidal) | High | High
13 | `uninitialized-state` | [Uninitialized state variables](https://github.com/crytic/slither/wiki/Detector-Documentation#uninitialized-state-variables) | High | High
14 | `uninitialized-storage` | [Uninitialized storage variables](https://github.com/crytic/slither/wiki/Detector-Documentation#uninitialized-storage-variables) | High | High
15 | `unprotected-upgrade` | [Unprotected upgradeable contract](https://github.com/crytic/slither/wiki/Detector-Documentation#unprotected-upgradeable-contract) | High | High
16 | `codex` | [Use Codex to find vulnerabilities.](https://github.com/crytic/slither/wiki/Detector-Documentation#codex) | High | Low
17 | `arbitrary-send-erc20-permit` | [transferFrom uses arbitrary from with permit](https://github.com/crytic/slither/wiki/Detector-Documentation#arbitrary-from-in-transferfrom-used-with-permit) | High | Medium
18 | `arbitrary-send-eth` | [Functions that send Ether to arbitrary destinations](https://github.com/crytic/slither/wiki/Detector-Documentation#functions-that-send-ether-to-arbitrary-destinations) | High | Medium
19 | `controlled-array-length` | [Tainted array length assignment](https://github.com/crytic/slither/wiki/Detector-Documentation#array-length-assignment) | High | Medium
20 | `controlled-delegatecall` | [Controlled delegatecall destination](https://github.com/crytic/slither/wiki/Detector-Documentation#controlled-delegatecall) | High | Medium
21 | `delegatecall-loop` | [Payable functions using `delegatecall` inside a loop](https://github.com/crytic/slither/wiki/Detector-Documentation/#payable-functions-using-delegatecall-inside-a-loop) | High | Medium
22 | `incorrect-exp` | [Incorrect exponentiation](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-exponentiation) | High | Medium
23 | `incorrect-return` | [If a `return` is incorrectly used in assembly mode.](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-return-in-assembly) | High | Medium
24 | `msg-value-loop` | [msg.value inside a loop](https://github.com/crytic/slither/wiki/Detector-Documentation/#msgvalue-inside-a-loop) | High | Medium
25 | `reentrancy-eth` | [Reentrancy vulnerabilities (theft of ethers)](https://github.com/crytic/slither/wiki/Detector-Documentation#reentrancy-vulnerabilities) | High | Medium
26 | `return-leave` | [If a `return` is used instead of a `leave`.](https://github.com/crytic/slither/wiki/Detector-Documentation#return-instead-of-leave-in-assembly) | High | Medium
27 | `storage-array` | [Signed storage integer array compiler bug](https://github.com/crytic/slither/wiki/Detector-Documentation#storage-signed-integer-array) | High | Medium
28 | `unchecked-transfer` | [Unchecked tokens transfer](https://github.com/crytic/slither/wiki/Detector-Documentation#unchecked-transfer) | High | Medium
29 | `weak-prng` | [Weak PRNG](https://github.com/crytic/slither/wiki/Detector-Documentation#weak-PRNG) | High | Medium
30 | `domain-separator-collision` | [Detects ERC20 tokens that have a function whose signature collides with EIP-2612's DOMAIN_SEPARATOR()](https://github.com/crytic/slither/wiki/Detector-Documentation#domain-separator-collision) | Medium | High
31 | `enum-conversion` | [Detect dangerous enum conversion](https://github.com/crytic/slither/wiki/Detector-Documentation#dangerous-enum-conversion) | Medium | High
32 | `erc20-interface` | [Incorrect ERC20 interfaces](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-erc20-interface) | Medium | High
33 | `erc721-interface` | [Incorrect ERC721 interfaces](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-erc721-interface) | Medium | High
34 | `incorrect-equality` | [Dangerous strict equalities](https://github.com/crytic/slither/wiki/Detector-Documentation#dangerous-strict-equalities) | Medium | High
35 | `locked-ether` | [Contracts that lock ether](https://github.com/crytic/slither/wiki/Detector-Documentation#contracts-that-lock-ether) | Medium | High
36 | `mapping-deletion` | [Deletion on mapping containing a structure](https://github.com/crytic/slither/wiki/Detector-Documentation#deletion-on-mapping-containing-a-structure) | Medium | High
37 | `shadowing-abstract` | [State variables shadowing from abstract contracts](https://github.com/crytic/slither/wiki/Detector-Documentation#state-variable-shadowing-from-abstract-contracts) | Medium | High
38 | `tautological-compare` | [Comparing a variable to itself always returns true or false, depending on comparison](https://github.com/crytic/slither/wiki/Detector-Documentation#tautological-compare) | Medium | High
39 | `tautology` | [Tautology or contradiction](https://github.com/crytic/slither/wiki/Detector-Documentation#tautology-or-contradiction) | Medium | High
40 | `write-after-write` | [Unused write](https://github.com/crytic/slither/wiki/Detector-Documentation#write-after-write) | Medium | High
41 | `boolean-cst` | [Misuse of Boolean constant](https://github.com/crytic/slither/wiki/Detector-Documentation#misuse-of-a-boolean-constant) | Medium | Medium
42 | `constant-function-asm` | [Constant functions using assembly code](https://github.com/crytic/slither/wiki/Detector-Documentation#constant-functions-using-assembly-code) | Medium | Medium
43 | `constant-function-state` | [Constant functions changing the state](https://github.com/crytic/slither/wiki/Detector-Documentation#constant-functions-changing-the-state) | Medium | Medium
44 | `divide-before-multiply` | [Imprecise arithmetic operations order](https://github.com/crytic/slither/wiki/Detector-Documentation#divide-before-multiply) | Medium | Medium
45 | `reentrancy-no-eth` | [Reentrancy vulnerabilities (no theft of ethers)](https://github.com/crytic/slither/wiki/Detector-Documentation#reentrancy-vulnerabilities-1) | Medium | Medium
46 | `reused-constructor` | [Reused base constructor](https://github.com/crytic/slither/wiki/Detector-Documentation#reused-base-constructors) | Medium | Medium
47 | `tx-origin` | [Dangerous usage of `tx.origin`](https://github.com/crytic/slither/wiki/Detector-Documentation#dangerous-usage-of-txorigin) | Medium | Medium
48 | `unchecked-lowlevel` | [Unchecked low-level calls](https://github.com/crytic/slither/wiki/Detector-Documentation#unchecked-low-level-calls) | Medium | Medium
49 | `unchecked-send` | [Unchecked send](https://github.com/crytic/slither/wiki/Detector-Documentation#unchecked-send) | Medium | Medium
50 | `uninitialized-local` | [Uninitialized local variables](https://github.com/crytic/slither/wiki/Detector-Documentation#uninitialized-local-variables) | Medium | Medium
51 | `unused-return` | [Unused return values](https://github.com/crytic/slither/wiki/Detector-Documentation#unused-return) | Medium | Medium
52 | `incorrect-modifier` | [Modifiers that can return the default value](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-modifier) | Low | High
53 | `shadowing-builtin` | [Built-in symbol shadowing](https://github.com/crytic/slither/wiki/Detector-Documentation#builtin-symbol-shadowing) | Low | High
55 | `uninitialized-fptr-cst` | [Uninitialized function pointer calls in constructors](https://github.com/crytic/slither/wiki/Detector-Documentation#uninitialized-function-pointers-in-constructors) | Low | High
56 | `variable-scope` | [Local variables used prior their declaration](https://github.com/crytic/slither/wiki/Detector-Documentation#pre-declaration-usage-of-local-variables) | Low | High
57 | `void-cst` | [Constructor called not implemented](https://github.com/crytic/slither/wiki/Detector-Documentation#void-constructor) | Low | High
58 | `calls-loop` | [Multiple calls in a loop](https://github.com/crytic/slither/wiki/Detector-Documentation/#calls-inside-a-loop) | Low | Medium
64 | `reentrancy-events` | [Reentrancy vulnerabilities leading to out-of-order Events](https://github.com/crytic/slither/wiki/Detector-Documentation#reentrancy-vulnerabilities-3) | Low | Medium
65 | `return-bomb` | [A low level callee may consume all callers gas unexpectedly.](https://github.com/crytic/slither/wiki/Detector-Documentation#return-bomb) | Low | Medium
66 | `timestamp` | [Dangerous usage of `block.timestamp`](https://github.com/crytic/slither/wiki/Detector-Documentation#block-timestamp) | Low | Medium
67 | `assembly` | [Assembly usage](https://github.com/crytic/slither/wiki/Detector-Documentation#assembly-usage) | Informational | High
68 | `assert-state-change` | [Assert state change](https://github.com/crytic/slither/wiki/Detector-Documentation#assert-state-change) | Informational | High
69 | `boolean-equal` | [Comparison to boolean constant](https://github.com/crytic/slither/wiki/Detector-Documentation#boolean-equality) | Informational | High
70 | `cyclomatic-complexity` | [Detects functions with high (> 11) cyclomatic complexity](https://github.com/crytic/slither/wiki/Detector-Documentation#cyclomatic-complexity) | Informational | High
73 | `function-init-state` | [Function initializing state variables](https://github.com/crytic/slither/wiki/Detector-Documentation#function-initializing-state) | Informational | High
74 | `incorrect-using-for` | [Detects using-for statement usage when no function from a given library matches a given type](https://github.com/crytic/slither/wiki/Detector-Documentation#incorrect-using-for-usage) | Informational | High
76 | `missing-inheritance` | [Missing inheritance](https://github.com/crytic/slither/wiki/Detector-Documentation#missing-inheritance) | Informational | High
77 | `naming-convention` | [Conformity to Solidity naming conventions](https://github.com/crytic/slither/wiki/Detector-Documentation#conformance-to-solidity-naming-conventions) | Informational | High
78 | `pragma` | [If different pragma directives are used](https://github.com/crytic/slither/wiki/Detector-Documentation#different-pragma-directives-are-used) | Informational | High
79 | `redundant-statements` | [Redundant statements](https://github.com/crytic/slither/wiki/Detector-Documentation#redundant-statements) | Informational | High
81 | `unimplemented-functions` | [Unimplemented functions](https://github.com/crytic/slither/wiki/Detector-Documentation#unimplemented-functions) | Informational | High
82 | `unused-state` | [Unused state variables](https://github.com/crytic/slither/wiki/Detector-Documentation#unused-state-variable) | Informational | High
83 | `costly-loop` | [Costly operations in a loop](https://github.com/crytic/slither/wiki/Detector-Documentation#costly-operations-inside-a-loop) | Informational | Medium
84 | `dead-code` | [Functions that are not used](https://github.com/crytic/slither/wiki/Detector-Documentation#dead-code) | Informational | Medium
85 | `reentrancy-unlimited-gas` | [Reentrancy vulnerabilities through send and transfer](https://github.com/crytic/slither/wiki/Detector-Documentation#reentrancy-vulnerabilities-4) | Informational | Medium
86 | `similar-names` | [Variable names are too similar](https://github.com/crytic/slither/wiki/Detector-Documentation#variable-names-too-similar) | Informational | Medium
87 | `too-many-digits` | [Conformance to numeric notation best practices](https://github.com/crytic/slither/wiki/Detector-Documentation#too-many-digits) | Informational | Medium
88 | `cache-array-length` | [Detects `for` loops that use `length` member of some storage array in their loop condition and don't modify it.](https://github.com/crytic/slither/wiki/Detector-Documentation#cache-array-length) | Optimization | High
89 | `constable-states` | [State variables that could be declared constant](https://github.com/crytic/slither/wiki/Detector-Documentation#state-variables-that-could-be-declared-constant) | Optimization | High
90 | `external-function` | [Public function that could be declared external](https://github.com/crytic/slither/wiki/Detector-Documentation#public-function-that-could-be-declared-external) | Optimization | High
91 | `immutable-states` | [State variables that could be declared immutable](https://github.com/crytic/slither/wiki/Detector-Documentation#state-variables-that-could-be-declared-immutable) | Optimization | High
92 | `var-read-using-this` | [Contract reads its own variable using `this`](https://github.com/crytic/slither/wiki/Detector-Documentation#public-variable-read-in-external-context) | Optimization | High
* The [Detector Documentation](https://github.com/crytic/slither/wiki/Detector-Documentation) for details on each detector
* The [Detection Selection](https://github.com/crytic/slither/wiki/Usage#detector-selection) to run only selected detectors. By default, all the detectors are run.
* The [Triage Mode](https://github.com/crytic/slither/wiki/Usage#triage-mode) to filter individual results
*`human-summary`: [Print a human-readable summary of the contracts](https://github.com/trailofbits/slither/wiki/Printer-documentation#human-summary)
*`inheritance-graph`: [Export the inheritance graph of each contract to a dot file](https://github.com/trailofbits/slither/wiki/Printer-documentation#inheritance-graph)
*`contract-summary`: [Print a summary of the contracts](https://github.com/trailofbits/slither/wiki/Printer-documentation#contract-summary)
*`loc`: [Count the total number lines of code (LOC), source lines of code (SLOC), and comment lines of code (CLOC) found in source files (SRC), dependencies (DEP), and test files (TEST).](https://github.com/trailofbits/slither/wiki/Printer-documentation#loc)
*`call-graph`: [Export the call-graph of the contracts to a dot file](https://github.com/trailofbits/slither/wiki/Printer-documentation#call-graph)
*`cfg`: [Export the CFG of each functions](https://github.com/trailofbits/slither/wiki/Printer-documentation#cfg)
*`function-summary`: [Print a summary of the functions](https://github.com/trailofbits/slither/wiki/Printer-documentation#function-summary)
*`vars-and-auth`: [Print the state variables written and the authorization of the functions](https://github.com/crytic/slither/wiki/Printer-documentation#variables-written-and-authorization)
*`not-pausable`: [Print functions that do not use `whenNotPaused` modifier](https://github.com/trailofbits/slither/wiki/Printer-documentation#when-not-paused).
* The [Printer documentation](https://github.com/trailofbits/slither/wiki/Printer-documentation) describes the information Slither is capable of visualizing for each contract.
Slither is licensed and distributed under the AGPLv3 license. [Contact us](mailto:opensource@trailofbits.com) if you're looking for an exception to the terms.
[MPro: Combining Static and Symbolic Analysis forScalable Testing of Smart Contract](https://arxiv.org/pdf/1911.00570.pdf) | Leverage data dependency through Slither | William Zhang, Sebastian Banescu, Leodardo Pasos, Steven Stewart, Vijay Ganesh | ISSRE 2019 | [MPro](https://github.com/QuanZhang-William/M-Pro)
[ETHPLOIT: From Fuzzing to Efficient Exploit Generation against Smart Contracts](https://wcventure.github.io/FuzzingPaper/Paper/SANER20_ETHPLOIT.pdf) | Leverage data dependency through Slither | Qingzhao Zhang, Yizhuo Wang, Juanru Li, Siqi Ma | SANER 20 | -
[Verification of Ethereum Smart Contracts: A Model Checking Approach](http://www.ijmlc.org/vol10/977-AM0059.pdf) | Symbolic execution built on top of Slither’s CFG | Tam Bang, Hoang H Nguyen, Dung Nguyen, Toan Trieu, Tho Quan | IJMLC 20 | -
[Demystifying Loops in Smart Contracts](https://www.microsoft.com/en-us/research/uploads/prod/2020/08/loops_solidity__camera_ready-5f3fec3f15c69.pdf) | Leverage data dependency through Slither | Ben Mariano, Yanju Chen, Yu Feng, Shuvendu Lahiri, Isil Dillig | ASE 20 | -
[Trace-Based Dynamic Gas Estimation of Loops in Smart Contracts](https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9268144) | Use Slither’s CFG to detect loops | Chunmiao Li, Shijie Nie, Yang Cao, Yijun Yu, Zhenjiang Hu | IEEE Open J. Comput. Soc. 1 (2020) | -
[SolType: Refinement Types for Arithmetic Overflow in Solidity](https://arxiv.org/abs/2110.00677) | Use Slither as frontend to build refinement type system | Bryan Tan, Benjamin Mariano, Shuvendu K. Lahiri, Isil Dillig, Yu Feng | POPL 22 | -
[Do Not Rug on Me: Leveraging Machine Learning Techniques for Automated Scam Detection](https://www.mdpi.com/2227-7390/10/6/949) | Use Slither to extract tokens' features (mintable, pausable, ..) | Mazorra, Bruno, Victor Adan, and Vanesa Daza | Mathematics 10.6 (2022) | -
[MANDO: Multi-Level Heterogeneous Graph Embeddings for Fine-Grained Detection of Smart Contract Vulnerabilities](https://arxiv.org/abs/2208.13252) | Use Slither to extract the CFG and call graph | Hoang Nguyen, Nhat-Minh Nguyen, Chunyao Xie, Zahra Ahmadi, Daniel Kudendo, Thanh-Nam Doan and Lingxiao Jiang| IEEE 9th International Conference on Data Science and Advanced Analytics (DSAA, 2022) | [ge-sc](https://github.com/MANDO-Project/ge-sc)
[Automated Auditing of Price Gouging TOD Vulnerabilities in Smart Contracts](https://www.cs.toronto.edu/~fanl/papers/price-icbc22.pdf) | Use Slither to extract the CFG and data dependencies| Sidi Mohamed Beillahi, Eric Keilty, Keerthi Nelaturu, Andreas Veneris, and Fan Long | 2022 IEEE International Conference on Blockchain and Cryptocurrency (ICBC) | [Smart-Contract-Repair](https://github.com/Veneris-Group/TOD-Location-Rectification)
If you are using Slither on an academic work, consider applying to the [Crytic $10k Research Prize](https://blog.trailofbits.com/2019/11/13/announcing-the-crytic-10k-research-prize/).